Em Tue, Apr 16, 2019 at 06:01:24PM +0200, Jiri Olsa escreveu: > By calling maps__insert we assume to get 2 references > on the map, which we relese within maps__remove call. > > However if there's already same map name, we currently > don't bump the reference and can crash, like: > > Program received signal SIGABRT, Aborted. > 0x00007ffff75e60f5 in raise () from /lib64/libc.so.6 > > (gdb) bt > #0 0x00007ffff75e60f5 in raise () from /lib64/libc.so.6 > #1 0x00007ffff75d0895 in abort () from /lib64/libc.so.6 > #2 0x00007ffff75d0769 in __assert_fail_base.cold () from /lib64/libc.so.6 > #3 0x00007ffff75de596 in __assert_fail () from /lib64/libc.so.6 > #4 0x00000000004fc006 in refcount_sub_and_test (i=1, r=0x1224e88) at > tools/include/linux/refcount.h:131 > #5 refcount_dec_and_test (r=0x1224e88) at > tools/include/linux/refcount.h:148 > #6 map__put (map=0x1224df0) at util/map.c:299 > #7 0x00000000004fdb95 in __maps__remove (map=0x1224df0, maps=0xb17d80) at > util/map.c:953 > #8 maps__remove (maps=0xb17d80, map=0x1224df0) at util/map.c:959 > #9 0x00000000004f7d8a in map_groups__remove (map=<optimized out>, > mg=<optimized out>) at util/map_groups.h:65 > #10 machine__process_ksymbol_unregister (sample=<optimized out>, > event=0x7ffff7279670, machine=<optimized out>) at util/machine.c:728 > #11 machine__process_ksymbol (machine=<optimized out>, > event=0x7ffff7279670, sample=<optimized out>) at util/machine.c:741 > #12 0x00000000004fffbb in perf_session__deliver_event (session=0xb11390, > event=0x7ffff7279670, tool=0x7fffffffc7b0, file_offset=13936) at > util/session.c:1362 > #13 0x00000000005039bb in do_flush (show_progress=false, oe=0xb17e80) at > util/ordered-events.c:243 > #14 __ordered_events__flush (oe=0xb17e80, how=OE_FLUSH__ROUND, > timestamp=<optimized out>) at util/ordered-events.c:322 > #15 0x00000000005005e4 in perf_session__process_user_event > (session=session@entry=0xb11390, event=event@entry=0x7ffff72a4af8, > ... > > Adding the map on the list and getting the reference event > if we find the map with same name.
Added: Fixes: 1e6285699b30 ("perf symbols: Fix slowness due to -ffunction-section") Ccing Eric Saint-Etienne <eric.saint.etie...@oracle.com>, the author of the patch that introduced that function. And applied to perf/urgent > Cc: Song Liu <songliubrav...@fb.com> > Link: http://lkml.kernel.org/n/tip-38t1ihcy32lvu4xfpm0p7...@git.kernel.org > Signed-off-by: Jiri Olsa <jo...@kernel.org> > --- > tools/perf/util/map.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c > index 28d484ef74ae..ee71efb9db62 100644 > --- a/tools/perf/util/map.c > +++ b/tools/perf/util/map.c > @@ -926,10 +926,8 @@ static void __maps__insert_name(struct maps *maps, > struct map *map) > rc = strcmp(m->dso->short_name, map->dso->short_name); > if (rc < 0) > p = &(*p)->rb_left; > - else if (rc > 0) > - p = &(*p)->rb_right; > else > - return; > + p = &(*p)->rb_right; > } > rb_link_node(&map->rb_node_name, parent, p); > rb_insert_color(&map->rb_node_name, &maps->names); > -- > 2.17.2 -- - Arnaldo